Development Of A Monitoring Systeminverse Of ? Beam By Inverse Compton Scattering

Shanghai Laser Electron Gamma Source(SLEGS)in the Shanghai Synchrotron Radiation Facility(SSRF)is a beam line station which will provide quasi monochromatic gamma-rays in the energy range of MeV by inverse Compton scattering between beams of CO2 laser photons and 3.5 GeV electrons from the Shanghai Light Source.It provides one of the best experimental platforms in the world for the research of optical nuclear physics,nuclear astrophysics,polarization physics,etc.SLEGS has an accurate and efficient gamma beam spot monitoring system,which can intuitively and effectively reflect the spatial distribution of gamma rays and is a common condition-supporting instrument for SLEGS and its physical experiments.In this paper,a high-precision and high-sensitivity inverse Compton y ray beam spot monitoring system for SLEGS was successfully developed by using gamma ray fluorescence imaging technology,which can effectively solve the alignment problem of inverse Compton ? ray source,collimator system and experimental instruments.Meanwhile,with the help of energy spectrum detector and beam intensity detector,the parameters and index information of LCS ? could be determined to realize the cross verification of light source performance.The main research contents and results are as follows:(1)Monte Carlo Geant4 was used to simulate calculation and optimization of the gamma ray fluorescence imaging system,and determine the optimization scheme of fluorescence imaging sensor for LYSO scintillator with a diameter of 76 mm and a thickness of 5 mm.On this basis,the optical component selection and optical path's specific parameters of the beam spot monitoring system were determined.(2)Solid works,a software,was used to optimize the overall mechanical structure of the beam spot monitoring device,the closed and compact darkroom of fluorescent light path and the camera obscura supporting system that can accurately adjust position.Meanwhile,the control software,data acquisition and analysis software of the beam spot monitoring device were developed.(3)The function and technical indicators of the beam spot monitoring device were tested and verified online by using the inverse Compton ? ray generated by SLEGS.By changing the energy size of the ray source and adjusting the aperture of the collimator system,cross comparison was made with the beam intensity detector at the front end.The system determined that the function and performance indexes of the device fully meet the requirements of line station,physical experiment and design.